A basic point about ko fights that isn't so often emphasised.
If your opponent is the first to capture in the ko, but you win the ko, that is effectively gaining sente. That is, with a long or short sequence like
etc., etc, ...
at the end we find White has sente, where Black began with sente.
Of course either of these may be true:
That is, the threat and the play finishing the ko may both be seen as open-ended plays.